Choosing the Right Recording Package
Think about the job first. A single supporting part is a very different request from a full arrangement with several keyboard layers.
Listen to your demo and mark where it feels empty. One gap usually needs one part; a song that needs texture, rhythm and a lead may need more.
Check the maximum duration of each package against the length of your song before you order.
If you are still undecided, send a message through the contact page and describe your project.